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View Full Version : How To Overhang rappel start with low ancher



Attila
07-12-2013, 08:28 AM
67805

I tried this last night for practice and found it quite difficult.

Since the anchor is near your feet, the rope is not holding you "up", only sideways. It makes for a sudden drop until the rope goes over the edge.

Leaning out until fully horizontal feels quite unnatural (and scary). It also feels like you're going to go down head first - and you actually might.

Also, you don't want to pinch your free hand between the rock and rope.

How do all-y'all approach this situation?

moab mark
07-12-2013, 08:29 AM
Go on your hip.

dude9478
07-12-2013, 08:30 AM
Go on your hip.

This...It may not be graceful but it works.

oldno7
07-12-2013, 08:47 AM
As stated, do a sliding butt start.

NEVER, under any circumstance, place yourself "above" an anchor as you have drawn.

Fall factors increase based on you're relationship in height to the anchor.

Stay low, incorporate rope friction into the system as quickly as possible. This is extremely important on marginal anchors.

oldno7
07-12-2013, 08:51 AM
This...It may not be graceful but it works.

If you're right handed--slide on your left hip--Left handed slide on right hip.

Once you get out to a vertical plane you can roll from your hip to your feet(if a wall is present)

If no wall(freehanging) keep sliding on your hip until free.

It can be quite graceful if done properly.

qedcook
07-12-2013, 09:12 AM
Just put a couple of bolts high up on the wall! :lol8: JK. Let's not get into that discussion again!

mzamp
07-12-2013, 09:32 AM
I sit on the edge facing out and then pivot around to my hip and off the edge letting just enough rope out to get the device past the lip. Until you get the hang of it the device usually ends up on top and then you have to finagle it over the lip which can be hard if you have nothing to push off of.

Udink
07-12-2013, 09:39 AM
I usually start out on my knees and crawl backward over the edge, making sure to keep my brake-hand and the rope well behind me and trying not to pin the rappel device between me and the rock. Once the rope between the anchor and me is horizontal, I transition from crawling to standing (or free-hanging, depending on the depth of the overhang).

dude9478
07-12-2013, 09:55 AM
One more thing to add, do not hold onto the rope above your rappel device. Good chance your hand will get stuck between the rock and your rope, I learned not to do that the hard way :)

Canyonater
07-12-2013, 09:55 AM
What you show in the diagram is very dangerous...loads the anchor significantly.....

ratagonia
07-12-2013, 10:45 AM
What you show in the diagram is very dangerous...loads the anchor significantly.....

Allow me to expand on this comment, and summarize the (good) discussion to date -

1. This is dangerous as a habit. The method shown places perhaps 3X perhaps 4X bodyweight on the anchor. If the anchor is very strong, this is not a problem, but anchors in canyoneering are often not very strong.

2. Because you are creating high loads, it is uncomfortable on your body. When doing this kind of start, beginners often stop at the point of maximum load and ask why it hurts so much, and what they are doing wrong. The answer being, of course, "stopping". More experienced rappellers move through this point rapidly.

3. Rappelling "softly" is a good skill to have for canyoneering.

4. The soft way to start this rappel has been outlined above. Sometimes kneeling works well (helps to have knee pads). But yes, usually I sit down on the edge with my feet over, and slide on over. Doing so gracefully is a sign of a skiller soft rappeller.

5. As Kurt indicated, it is a good idea to keep your brake hand on the outside, so you roll over your non-brake-hand hip.

6. Give people a bottom belay when they are doing this, okay?

7. Don't place your hand on the rope above your device. Use your hand pushing on the rock. Many of us have learned this the hard way. If helpful, for all but the last person, webbing or a short end of rope can be rigged for people to grasp as they worm their way over the edge.

Tom :moses:

oldno7
07-12-2013, 12:32 PM
Just put a couple of bolts high up on the wall! :lol8: JK. Let's not get into that discussion again!

While your comment was entirely made in jest, and I liked it, let me point something out.

Not all bolted anchors are created equal!!!!

The only person who is ever "certain" of the quality of bolt placement, is the person who installed the bolt.

Was the rock solid or hollow sounding?

Was the bolt a 5-piece,3-piece,glue in, hardware store variety or ???

Was the hole properly drilled and cleaned?

Was the bolt 2" long, 3 3/4, 6"?

Are you looking at an internally threaded bolt or externally threaded, does it somehow matter?

Were they placed in shear or tension??

Do the hangars spin? Does it matter??

While it is too easy for us all to get in a hurry going through a trade route/bolted canyon and take bolted anchors for granted,

The prudent canyoneer who likes himself and his friends, will do a bit of examining at each anchor to evaluate it's worthiness.

If I'm not sure about answers to all the above question's, I might treat a bolted anchor as a marginal one.(rapped off many that were marginal)

Just something to ponder.

Brian in SLC
07-12-2013, 03:11 PM
My technique is to sit at or as close downhill from the anchor as possible. Rig rappel. Keep my tether clipped to the anchor. Cinch up and load the rappel, making sure, double checking that I'm properly rigged. Unclip the tether. I butt skootch (tm) until I'm at the edge, then, outside hand on the rope, roll onto my hip and push off with my guide hand. Over the lip we go.

I hate those kinda starts.

If I'm super confident of the rock edge (not being sharp), anchor and my rigging, I'll walk down and jump off softly. Usually with crampons and covered with ice climbing gear...ha ha. (Referring to the standard rappel off Scruffy Band in Little Cottonwood). I still hate it.

Iceaxe
07-12-2013, 03:56 PM
Usually with crampons and covered with ice climbing gear...ha ha.

Nothing like jumping off a cliff with dozens of razor sharp daggers strapped to your body. :lol8:

canyonguru
07-12-2013, 04:00 PM
I like to lean way back and they jump off backwards, let off of my brake hand until i am under the ledge then slow my self down. Terrible way of doing it but it works. I only do this on canyons i am very farmilar with and i know what is under the ledge, but most of the time i do as described above. its really only the way to do it safely and to not damage the rope or the anchor in the process.

bjp
07-12-2013, 04:04 PM
The method shown places perhaps 3X perhaps 4X bodyweight on the anchor.

Because I know everyone is dying to know whether it's 3X or 4X, here are the actual forces:
67807

The colored lines represent ropes anchored at various distances from the rappeller (and they're drawn approximately to scale). The purple rope's anchor is as far from the stick figure's feet when he's standing up straight as his belay device is above the ground. As drawn, the stick figure is at a 26 degree angle from standing up straight. From blue to light blue, the rope anchors are 0.2x, 0.5x, 0.75x, 1x, 1.5x, 3x, and 10x the-height-of-the-belay-device-while-standing away from the stick figure's feet.

The force on the anchor goes to infinity when the rappeller is horizontal, but that's just another way of saying you absolutely must move your feet before your device is horizontal with the edge or else you'll swing through that position.

The formula generating those graphs is
67808
...where r is the ratio between anchor distance (rappeller's feet to anchor) and the height of the belay device when standing up straight, and theta is the angle relative to standing up straight.

moab mark
07-12-2013, 09:20 PM
Thanks for the diagram.